67-72 Electric speedo

[ls1nova71]

This is my 120mph electric speedo mod for 67-72 trucks. I got the idea from another member on here, brad_man_72, when I saw his truck at the All Truck Nationals several years ago. He had it in his truck, but it wasn't working. I took the ball and ran with it.

What it is, is the guts from a '96-7 S-10. They made two speedos in those trucks, one with a tach and one without. You need the one without the tach. The S-10 speedo goes from 0 to 100mph, but the numbers start at what would be the 8 o'clock position and go to the 4 o'clock position. 67-72 trucks, the 0mph is at the 7 o'clock position and goes to the 5 o'clock position, so for it to work right and to have the exact same sweep, the needle needed to be put on in the 7 o'clock position, but what that does is put the 100mph mark at 3 o'clock, so I added 110 and 120 to even everything out. I had a new face made up that has the correct lines on it, one for every 10 mph, and then had a "mask" made to be able to repaint on the numbers on the lens.

Mounting the guts behind the original face is probably the hardest part. Actually using the original face didn't work out as well as just using the S-10 face and putting the new face I had made right on top of it. Once I put the new face on, I cut out the odometer and trip odometer holes. I had to move a couple of the dash light bulbs, and I did away with the printed circut and just hard wired them with a plug so I can unplug the whole cluster to remove it. I also put a small red LED in the factory spot for the high beam indicator.

You wouldn't need to keep the trip odometerm but I figured since it was there I would try and keep it. It is just barely noticeable, but the reset knob is just to the right of the speedo in the bezel.

The pics here are of it when I was working on it, it's not done in the pics and I have since had the lines on the face changed to more of a greenish tint to match the other gauges because the first ones looked too white next to them.

I have tested this speedo by hooking it up to my 2003 Sunfire, and it was right on with what the sunfire speedo read, so I know it's going to work when I get my truck on the road.